The aim of the present study was to correlate laboratory data and postprocedural parameters after conventional transarterial chemoembolization (cTACE) for hepatocellular carcinoma (HCC) with the radiological response. The study consisted of a retrospective analysis of prospectively collected data from 70 consecutive patients who underwent cTACE. Laboratory parameters were assessed daily after cTACE and compared to pretreatment values. Post-treatment radiological response was assessed using mRECIST at one month from cTACE, and factors associated with treatment response (complete and objective response) were assessed by logistic regression analysis. The optimal cutoff points in predicting the complete response of target lesions were a 52% ALT and a 46% AST increase after cTACE compared to the pre-treatment values. Using multivariate analyses, >46% AST and >52% ALT increases with respect to the pre-treatment value were significantly correlated with the objective response (p = 0.03 and p = 0.04, respectively) and the complete response (p = 0.02 and p = 0.02, respectively). No patients experienced liver function deterioration after cTACE, and no specific treatment was required. This study showed that post-treatment transient transaminase elevation was predictive of objective response to superselective cTACE in clinical practice, representing a simple tool to guide treatment strategy of HCC patients in a tailored approach.